lsst.pipe.tasks.coaddBase Namespace Reference

Classes
class	CoaddBaseConfig
	Configuration parameters for CoaddBaseTask. More...
class	CoaddBaseTask
	Base class for coaddition. More...
class	CoaddTaskRunner
class	SelectDataIdContainer
	A dataId container for inputs to be selected. More...

Functions
def	getSkyInfo (coaddName, patchRef)
	Return the SkyMap, tract and patch information, wcs, and outer bbox of the patch to be coadded. More...
def	makeSkyInfo (skyMap, tractId, patchId)
def	scaleVariance (maskedImage, maskPlanes, log=None)
	Scale the variance in a maskedImage. More...
def	makeCoaddSuffix (warpType="direct")

Function Documentation

getSkyInfo()

def lsst.pipe.tasks.coaddBase.getSkyInfo	(		coaddName,
			patchRef
	)

Return the SkyMap, tract and patch information, wcs, and outer bbox of the patch to be coadded.

Parameters

[in]	coaddName	coadd name; typically one of deep or goodSeeing
[in]	patchRef	data reference for sky map. Must include keys "tract" and "patch"

Returns

pipe_base Struct containing:

• skyMap: sky map
• tractInfo: information for chosen tract of sky map
• patchInfo: information about chosen patch of tract
• wcs: WCS of tract
• bbox: outer bbox of patch, as an geom Box2I

Definition at line 261 of file coaddBase.py.

def getSkyInfo(coaddName, patchRef):
    """!
    @brief Return the SkyMap, tract and patch information, wcs, and outer bbox of the patch to be coadded.
 
    @param[in]  coaddName  coadd name; typically one of deep or goodSeeing
    @param[in]  patchRef   data reference for sky map. Must include keys "tract" and "patch"
 
    @return pipe_base Struct containing:
    - skyMap: sky map
    - tractInfo: information for chosen tract of sky map
    - patchInfo: information about chosen patch of tract
    - wcs: WCS of tract
    - bbox: outer bbox of patch, as an geom Box2I
    """
    skyMap = patchRef.get(coaddName + "Coadd_skyMap")
    return makeSkyInfo(skyMap, patchRef.dataId["tract"], patchRef.dataId["patch"])
 
 

makeCoaddSuffix()

def lsst.pipe.tasks.coaddBase.makeCoaddSuffix

(

warpType = "direct"

)

Return coadd suffix for warpType

Parameters
----------
warpType : string
    Either 'direct' or 'psfMatched'

Returns
-------
CoaddSuffix : `string`

Definition at line 336 of file coaddBase.py.

def makeCoaddSuffix(warpType="direct"):
    """Return coadd suffix for warpType
 
    Parameters
    ----------
    warpType : string
        Either 'direct' or 'psfMatched'
 
    Returns
    -------
    CoaddSuffix : `string`
    """
    suffix = "" if warpType == "direct" else warpType[0].upper() + warpType[1:]
    return suffix

makeSkyInfo()

def lsst.pipe.tasks.coaddBase.makeSkyInfo	(		skyMap,
			tractId,
			patchId
	)

Return SkyInfo Struct

Constructs SkyInfo used by coaddition tasks for multiple
patchId formats.

Parameters
----------
skyMap : `lsst.skyMap.SkyMap`
tractId : int
patchId : str or int or tuple of int
    Either Gen2-style comma delimited string (e.g. '4,5'),
    tuple of integers (e.g (4, 5), Gen3-style integer.

Definition at line 279 of file coaddBase.py.

def makeSkyInfo(skyMap, tractId, patchId):
    """Return SkyInfo Struct
 
    Constructs SkyInfo used by coaddition tasks for multiple
    patchId formats.
 
    Parameters
    ----------
    skyMap : `lsst.skyMap.SkyMap`
    tractId : int
    patchId : str or int or tuple of int
        Either Gen2-style comma delimited string (e.g. '4,5'),
        tuple of integers (e.g (4, 5), Gen3-style integer.
    """
    tractInfo = skyMap[tractId]
 
    if isinstance(patchId, str) and ',' in patchId:
        #  patch format is "xIndex,yIndex"
        patchIndex = tuple(int(i) for i in patchId.split(","))
    else:
        patchIndex = patchId
 
    patchInfo = tractInfo.getPatchInfo(patchIndex)
 
    return pipeBase.Struct(
        skyMap=skyMap,
        tractInfo=tractInfo,
        patchInfo=patchInfo,
        wcs=tractInfo.getWcs(),
        bbox=patchInfo.getOuterBBox(),
    )
 
 

scaleVariance()

def lsst.pipe.tasks.coaddBase.scaleVariance	(		maskedImage,
			maskPlanes,
			log = None
	)

Scale the variance in a maskedImage.

The variance plane in a convolved or warped image (or a coadd derived from warped images) does not accurately reflect the noise properties of the image because variance has been lost to covariance. This function attempts to correct for this by scaling the variance plane to match the observed variance in the image. This is not perfect (because we're not tracking the covariance) but it's simple and is often good enough.

Deprecated:

Use the ScaleVarianceTask instead.

Parameters

maskedImage	MaskedImage to operate on; variance will be scaled
maskPlanes	List of mask planes for pixels to reject
log	Log for reporting the renormalization factor; or None

Returns

renormalisation factor

Definition at line 312 of file coaddBase.py.

def scaleVariance(maskedImage, maskPlanes, log=None):
    """!
    @brief Scale the variance in a maskedImage
 
    The variance plane in a convolved or warped image (or a coadd derived
    from warped images) does not accurately reflect the noise properties of
    the image because variance has been lost to covariance. This function
    attempts to correct for this by scaling the variance plane to match
    the observed variance in the image. This is not perfect (because we're
    not tracking the covariance) but it's simple and is often good enough.
 
    @deprecated Use the ScaleVarianceTask instead.
 
    @param maskedImage  MaskedImage to operate on; variance will be scaled
    @param maskPlanes  List of mask planes for pixels to reject
    @param log  Log for reporting the renormalization factor; or None
    @return renormalisation factor
    """
    config = ScaleVarianceTask.ConfigClass()
    config.maskPlanes = maskPlanes
    task = ScaleVarianceTask(config=config, name="scaleVariance", log=log)
    return task.run(maskedImage)